/Engine/Source/Runtime/Engine/Classes/Components/SceneCaptureComponent2D.h
Adds an Blendable (implementsIBlendableInterface) to the array of Blendables (if it doesn't exist) and update the weight
void AddOrUpdateBlendable ( [TScriptInterface](API\Runtime\CoreUObject\UObject\TScriptInterface)< [IBlendableInterface](API\Runtime\Engine\Engine\IBlendableInterface) > InBlendableObject, float InWeight )